Electrical apparatus



Aug. 25, 1964 c. w. ROOT 3,145,700

ELECTRICAL APPARATUS Original Filed Feb. 28, 1958 3 Sheets-Sheet 1 INVENTOR C/MZPZAS :14 007 (gall MA/ L ATTOR EY's Aug. 25, 1964 c. w. ROOT ELECTRICAL APPARATUS 3 Sheets-Sheet 3 Original Filed Feb. 28, 1958 United States Patent ()ffice 3,145,700 Patented Aug. 25, 1964 3,145,700 ELECTRICAL APPARATUS Charles W. Root, Sidney, N.Y., assignor to The Bendix Corporation, Sidney, N.Y., a corporation of Delaware Original application Feb. 28, 1958, Ser. No. 718,177, new

Patent No. 3,013,129 dated Dec. 12, 1961. Divided and this application Feb. 27, 1961, Ser. No. 91,854

- Claims. (Cl. 123-179) This invention relates to electrical apparatus, and more particularly to a novel electrical circuit, such as an engine starting and ignition circuit.

This applicationis a division of application Serial No. 718,177, filed February 28, 1958, now Patent No. 3,- 013,129,

The invention has among its objects the provision of a novel circuit of the type indicated.

Another object of the invention lies in the provision of such circuit which is easily controlled, said circuit including a selectively energized auxiliary circuit for the operation of one or more accessory devices.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention.

' In the drawings, wherein like reference characters refer to likeparts throughout the several views,

FIG. 1 is a view in axial section through an ignition switch which may be employed in a circuit in accordance with the invention, the switch rotor being shown in the run position, certain parts of the switch being shown in elevation and other parts thereof being broken away for clarity of illustration, the section being taken along line 1--1 of FIG. 2,;

FIG. 2; is a view in rear elevation of the switch of FIG. 1;

FIG. 3 is a View in transverse section through the switch of FIG. 1, the movable contacts of the switch being shown in phantom lines in the run position of theswitch, the section being taken along the line 33 of FIG. 1;

FIG. 4 is a view in transverse section through the switch, the rotor being shown in therun position of FIG. 1, the section being taken generally along the line 44 of FIG. 1; FIG. 5 is a view in longitudinal section a switch of FIG. 1, the section being taken generally along the lines-5 of FIG. 4, the switch rotor and the conthrough the I tacts carried thereby being shown intheir normal run position;

FIG. 6 is a view in longitudinal section through the switch with the rotor thereof in its .run position but with such rotor axially displaced so as to energize an auxiliary circuit, the section being taken generally along theline 6--6 of FIG. 4; a

FIG. 7 is a view in transverse section through the switch with the rotor thereof in run position, the section being taken generally along the line 77 of FIG. 1;

FIG, 8 is a view in transverse section through the mounting and locking mechanism of the switch, the central, switch-locking mechanism being omitted for simplicity, the rotor of the switch being shown in run position, the section being taken along the line 8-8 of FIG. 1; and v FIG. 9 is a wiring diagram of a circuit in accordance with the invention, the circuit being an ignition circut incorporating a switch of the type shown in FIGS. 1-8, inclusive, the switch being shown somewhat diagrammatically in perspective.

. and a second (start) contact 34.

The switch'illustrated herein is incorporated in a circuit in accordance with the invention, said circuit controllingstarting and choking circuits of an internal com bustion engine. In such application the embodiment of switch illustrated provides positive off and on control of high or low tension magnetos or of battery ignition, and a selectively operated choke arrangement where'- by the engine can be choked in a desired number of operative positions of the switch. In the embodiment shown, the switch also provides a locking mechanism, giving theft-proof security, and incorporates a spring loaded mechanism that automatically returns thefswitch rotor to the running or run position following its turning into the starting or start position. In the illustrative embodiment, the construction of the switch is such that it can be operated to choke the engine in both the start and the run positions, merely by axial displacement of the switch rotor from its normal axial position. As a consequence of such features, the switch permits a simple, one-handed operation thereofto' start, choke, or stop the engine. The switch illustrated herein is disclosed and claimed in the aforesaid U.S. Patent No. 3,013,129.

Turning now to the drawings, there is shown therein a switch, generally designated'l't), which is useful, for

example, as the ignition switch of an outboardmotor.

Switch 10 has a housing, made for example of metal, having a rear hollow cup-like portion 11 and a forward mounting and locking barrel receiving portion 12 generally coaxial with portion 11. The cavity 15 in portion 11 contains a switch rotor 16, to be described, carrying a plurality of rotor contacts; barrel 12 contains a key actuated locking cylinder 19 rotatable in bore 17 of barrel 12 and made fast to the switch rotor, whereby the switch may be operated by a lockingkey 98. The rear end of portion 1170f the housingis closed by a transversely extending electrically insulating stator plate 14 which carries a plurality of stator contacts selectively cooperating with the rotor contacts.

As will be seen in FIGS. 1, 5, 6, and 7, the locking cylinder 19 has a generally square central tang 20 on its rear end, the tang being retained by a screw 21 in a central passage 22 of generally square cross section snugly receiving the tank 20. To permit the mounting of locking cylinder 19 in only one angular position with respect to the switch rotor, two. adjacent edges of tang 20 are bevelled, and the corresponding two corners ofpassage 22 in the rotor have a straightfillet, as shown in FIG. '7. The switch may be mounted, for example, on a switch board or panel,. not shown, by having barrel 12 extend through a hole in such board or panel, an inner or rear nut 24 and an outer or forward nut 25 mounted on threads 26 on barrel 12 being adapted to overlie and engage the respective sides of the board or panel.

As shown in FIGS. 2, 3, and 4, the stator contact plate 14 and the rear portion 11 of the switch housing are provided withmating ears, the plate being retained onthe housing by studs 27 extending through'holes in the ears of the plate and into threaded blind'holes in the ears 29 on portion'llof the housing.

In the embodiment of switch shown, the switch rotor as molded resin, for example, has two oppositeextending generally similar broad wings 30 and 31 lying generally radially of the rotor. Wing 30, lying at the bottom in FIGS. 1 and 4, serves to support a first (run) contact 32 Wing 31,; lying at the top in FIGS. 1 and 4, serves to support a third, selective- 1y operated (choked) contact 35. Contacts 32 and 34 are similar, and, as will appear, are operative at all times then the switch rotor is in its normal, axially outer position and is turned into the respective angular run and start positions. The choke contact 35 is operative only when it is in either its start or run angular positions and the rotor is thrust into its axially inner position (FIG. 6). To permit the described axial movement of the switch rotor, the cavity in housing portion 11 is made with an axial length somewhat exceeding the axial length of the switch rotor.

Since contacts 32 and 34 and their manner of mounting in the switch rotor are similar, detailed description thereof will be confined to contact 34, which is best shown in FIG. 1. Contact 34 is a generally U-shaped sheet metal member which has a rectangular body configuration, the body being axially reciprocably received in a rearwardly open blind passage 37 in wing of the rotor. The body of contact 34 and the section of passage 37 are generally the same, so that the contact is non-rotatably held with respect to the rotor. The forward, blind end of passage 37 is of reduced diameter at 39, so as to form a seat for a coil compression spring 40 disposed in passage 37 and held compressed between the closed end of the passage and the transverse bight portion of contact 34. The large rear, open end of passage 37 is axially long enough to receive the contact 34 therewithin when the switch rotor is axially displaced rearwardly into the enginechoking position of FIG. 6.

The body of contact 34 has oppositely extending feet 41 and 42 lying in the same transverse plane, foot 41 being peripherally extended as shown in FIG. 4 so that it has wing portions at both sides of the body of the contact 34. Foot 42 is of the same width as the body of contact 34. The feet 41 and 42, which constitute contacts proper, lie in engagement with the inner face of contact plate 14, or with the inner faces of the respective stator contacts, at all times. a

Contact 32 has a U-shaped body 44 which is slidably and non-rotatably received in a rectangular blind passage 45 in-wing 30 of rotor 16. A coil compression spring 46 disposedin the smaller inner end 48 of passage 45 between the closed end thereof andthe bight of contact body 44 urges such body in an axially outwardly direction. The outer free ends of body 44 are bent oppositely to form an outer foot or contact proper 47 and an inner foot or contact proper 49. Feet 47 and 49 have the same width as the body 44 of contact 32.

The-stator plate 14 is provided with a central circular contact 50 coaxial of the switch rotor. Contact 50 is embedded in plate 14 so that the inner face of the contact lies flush with the inner face of plate 14. As shown in FIGS. 1, 3, and 6 the inner contacts proper 42 and 49 overlie and engage at all times the central circular stator contact 50.'- A headed stud or rivet 51 extends centrally through contact 50 and stator plate14, stud 51 serving to secure a central terminal 52 on the outer face of plate 14.

The various other stator contacts of the illustrative switch are shown most clearly in FIG. 3. All such contacts have their inner faces lying flushwith the inner face of plate14. Such contacts will be described in connection with their function when the switch is employed as an engine ignition switch in the manner to be described in connection with FIG. 9. Proceeding clockwise from the bottom of FIG. 3, the stator plate 14 is provided with a first run contact 54' and a second run contact 55, the inner operative portions of which lie in an elongated recess in the inner face of plate 14. Contacts 54 and 55' are in the form of headed studs projecting through plate 14, the inner surfaces of the heads lying flush with the inner surface of the plate. The outer ends of the studs of such contacts, lying at the rear of plate 14, are connected by a strap conductor member 56; a terminal 57 is connected'to the outer end of contact 54. The outer ends of thestud portions of contacts 54 are headed to retain strap connector 56and terminal 57. Contacts 54 and 55 are so located angularly about the axis of plate 14 that when the switch rotor is in a run position the contact 47 thereof, shown in phantom lines in FIG. 3,

partially overlies both contacts 54 and 55. In such run position the starting contact 34 lies at the bottom of FIG. 3 in inoperative position.

Stator plate 14 is provided with a third contact 59 in the form of a stud having an enlarged head positioned in a recess in the inner face of the plate. Contact 59 has its stud portion extending through plate 14, the outer end of the stud being connected to a terminal 60. Contact 59, which is interposed in the starter circuit, is so spaced angularly about the axis of plate 14 that when the switch rotor is turned clockwise (FIG. 3) into its starting position, contact 47 overlies contact 59. It will also be seen that when the rotor is so turned contact 41 overlies contacts 54 and 55.

Stator plate 14 is further provided with two angularly spaced choke contacts 61 and 62, the latter of such contacts being positioned substantially diametrically opposite contact 54. In the illustrative embodiment, contacts 61 and 62, which likewise are made in the formof headed studs, are connected at their outer ends by a strap conductor member 64, there being a. terminal 65 connected to contact 62 whereby contacts 61 and 62 may be connected to a choke circuit. Contacts 61 and 62 are spaced angularly about the axis of plate 14 so that the choke contact 35 on the switch rotor is aligned with contact 61 when the rotor is in the run position, and is aligned with contact 62 when the rotor is in the startposition. 7

As shown most clearly in FIG. 4 the wing 31 of switch rotor 16 supports said choke contact 35 diametrically opposite contact 34. Contact 35 has a generally U-shaped body 66 which is slidably and non-rotatably received in a blind passage 67 in wing 31. 'The inner end 69 of passage 67 is of slightly reduced cross section and serves to retain a coil compression spring 70, the inner and outer ends of which engage the closed end of passage 67 and the bight of body 66 of contact 35, respectively] A pin 71 extends through a portion of wing 31 centrally across the outer larger end of passage 67 to' engage the bight of contact body 66, whereby to restrain movement of contact 35 axially outwardly of the position shown in FIG;

I thereby when the switch rotor is in its normal axially inner position shown in FIG. 1. I The switch rotor is normally held in such axially inner position by the coil compression springs 46 and 40 of contacts 32 and 34, respectively, such springs functioning by thrusting their contacts against plate 14 to thrust the switch rotor to the right (FIG. 1). As shown, theouter contact proper 74 of contact 35 is axially aligned with stator contacts 61 and 62 when the switch rotor is in the run and start positions, respectively. The inner choke contact proper 72 is axially aligned with the central stator contact 50. It will be seen, therefore, that when the switch rotor is thrust to the left (FIG. 1), after it has been turned to the proper position, contact 35 will operatively connect contact 50 with either contact 61 or 62;

The switch is provided with a switch rotor positioning means whereby the rotor stably remains in both the off and run" positions when it is turned thereinto, and which automatically returns the rotor from the start to the run position when the rotor is released after having been turned to start position. Such positioning of the switch rotor is provided by the following means. A coil torque-providing spring 75 is disposed within housing: portion 11 of the switch and is loosely received in a seat on the switch rotor 16 having a spring'positioning p shoulder 73 Spring 75 has a radially inwardly directed tang 76 (FIG. 4) which overlies the right hand edge of wing of the rotor. The other end of spring 75 has a tang 77 extending parallel to the axis of the rotor and abutting the left hand edge of a shallow boss 79 projecting inwardly into cavity 15 of the switch housing. Spring 75 opposes turning of the switch rotor from the off position toward the run and start positions thereof.

The switch rotor is stably held in either of its off or its run positions, by a leaf spring 80 which has its outer end 81 secured against the inner surface of housing portion 11 by a rivet 82, as shown in FIG. 7. Spring 86 inclines inwardly somewhat toward the switch rotor, the inner end of the spring being curved at 84 to provide a detent. The rim of switch rotor 16 in the transverse zone thereof aligned with spring 80 is provided with two circumferentially spaced detent-receiving curved depressions 85 and 86. Detent 84 lies in recess 85, as shown in FIG. 7, when it is in its run position. When the switch rotor is turned clockwise (FIG. 7) from the position shown in FIG. 7, detent 84 rides up out of recess 85 and, when the rotor has reached its start position, is received in depression 86. In this position of the rotor the spring 75 will have been wound suificiently to overcome the retardation imposed on the rotor by engagement between the detent 84 and recess 86. Thus when the switch rotor is released from its start position, spring 75 returns it to the run position. The engagement between the detent 84 and reces 85, however, is sufiicient stably to retain the rotor in its run position unless it is manually turned therefrom into either the start or of? position. When the rotor is turned counterclockwise (FIG. 7) into its oil position, detent 84 rides up out of recess 85 and onto a part-cylindrical surface 87 on the rotor until it comes into engagement with a shoulder 89 on the rotor.

The described turning of the switch rotor from the off into either the run or start positions, and from the run to the o position, iseffected by a key 98 inserted in a conventional cylindrical lock, not specifically shown, positioned in lock barrel 19. The inner wall 17 of barrel 12 0f the switch housing is provided with two diametrically opposite axially extending grooves 92 (FIGS; 6 and 8), one of which selectively receivesthe locking dogs of the lock when the key 98 is withdrawn and the switch rotor is in o position.

Theouter end, of the lock barrel 19, which is secured to the switch rotor, and the outer end of the housing barrel 12 constitute means whereby barrel 19 and the rotor 16 attached thereto are locked into their axially inner position (at the right in FIG. 1) when the switch rotor is .in off position, but arefree to be thrust into their axially outer position (atthe left in FIG. 6) when the switch rotor is in either its run or start position.

In the embodiment shown, such means takes the form of a semi-circular groove 94 at the outer end of mount ing barrel 12 and a terminal flange 95 on the inner end of lock barrel 19. Flange 95 has an axially thickened portion 96 which extends circumferentially of the locking barrel throughout an angular extent which is less than that of groove 94 by an amount somewhat greater than the angle between the run and start positions of the switch rotor. The groove 94 and the thickened portion 96 of the flange on the locking barrel are so oriented and related that when the switch rotor is in the off position a part of the thickened portion of the flange overlies the ungrooved part of the end of barrel 12, thereby preventing axially outward movement of the switch rotor. The groove 94 and the thickened portion 96 of the flange are further so related'that portion 96 of the flange lies within the projection of, or within groove 94, when the switch rotor is in either its run or start position. The axially extending edges of the groove 94 and of the thickened portion 96 of the flange on the locking barrel function as positive stops when the switch rotor is thrust out wardly, to confine angular motion of the rotor in such axial position between the run and start positions.

In FIG. 9 there is shown an ignition and starting circuit for a two-cylinder engine such as an outboard motor. Such motor (not shown) is provided with an electrical starting motor 100 which is selectively energized by a starting relay 101. The engine is also provided with a magneto and current distributing device which may be, for example, of the type disclosed in Dingman, US. Patent No. 2,930,826. The output wires from such device may be selectively short circuited, torender the magneto 102 thereof inoperative, by a relay 104. The engine is also provided with an engine choking device (not shown) operated by a relay generally shown at 105. A source of direct current such as a battery 106 is'provided for the engine. The illustrative switch 110 shown somewhat diagrammatically in FIG. 9 is connected to the relays and the battery so that the relays are deenergized when the switch is in its off position. Relay 104 is energized to remove the short circuit across the output of magneto 102 when the switch rotor is in either its start or run position, the starting relay 101 is energized when the switch is in its start position, and the relay 105 is energized to choke the engine when the switch rotor is in either its fstart or run positions andis thrust axially outwardly.

Proceeding now to a detailed description of the'circuit of FIG. 9, there is preferably provided a detachable conhector 99 which readily allows the engine, bearing the portion of the circuit to the left of connector 99, to be removed from its support such as a boat. A wire 107 is connected to the negative terminal of battery 106and to ground, which may be the frame of the engine. A wire 109 is connected to the posiitve terminal of battery 106, and extends 'to one contact of switch 114 of relay 101 where it is joined to a wire 111 leading to the central stator contact 50. A wire 112 leads from starter contact 59 on the stator to one end of the coil 113 of relay101. The other end of such coil is grounded. It will thus be seen that when contact 32 is positioned to extend between contacts 50 and 59 (in the start position of the switch) starter switch 114 is closed. The motor 110, which has one terminal connected to ground and the other connected to switch 114 through wire is thus energized to start the engine. Coil 115 of ignition relay 104 has one terminal thereof connected to ground and the other terminal connected to contacts 54 and 55 by wire 116. As we have seen when the switch is in its run position, contacts 50 and 54, 55 are bridged by motor contact 32, and when the switch is inthe start position contacts 50 and 54, 55 are bridged by rotor contact 34. Accordingly, in both positions of the switch, relay 104 is energized to retract movable contact 117, thereby to remove the short circuit between wires 119 and 120 connected to the leads of the magneto whereuponthe magneto delivers timed electrical impulses to discharge devices such as spark plugs diagrammatically indicated at 121 and 122.

Choke contacts 61 and 62 on the stator are connected to one terminal of the coil 125 of choke relay 105 by wire 124. Theother end of such coil is connected to ground. When the switch rotor is turned so as to be aligned with either of contacts 61 and 62, that is, when it lies in either of its run or start positions, the rotor may be thrust axially outwardly so'that its contact 35 bridges stator contact 50 and the respective one of contacts 61 and 62, thereby to energize relay 105 to choke the motor.

Although a'rotary switch has been illustrated in the circuit of FIG. 9 of the drawings and described in the foregoing specification, it is to be expressly understood that other types of switches or a combination of other types of switches may be employed in the circuit of FIG. 9 to perform the described circuit closing and opening functions without departing from the spirit and scope of the invention as will now be apparent to those skilled inthe art.

What is claimed is:

1. A control system comprising a first circuit, a second circuit, a third circuit, and a switch operable selectively to deenergize said three circuits simultaneously, to energize only the first circuit, or to energize the first and second circuits simultaneously, and operable selectively to energize the third circuit simultaneously with either the energization of the first circuit or with the simultaneous energization of the first and second circuits, said switch comprising a stator having a first set of contacts comprising a first contact in said first circuit, a second contact in said second circuit, and a third contact in said third circuit, a switch element which may be selectively moved relative to the stator to first, second, and third positions, said movable switch element having a second set of contacts at least one of which engages the first contact in the third position of the movable switch element and at least one of which engages the second and first contacts in the third and second positions respectively of the movable switch element, the movable switch element having a fourth contact confronting the third contact when the movable switch element is in its third and second positions, means connecting the second set of contacts and the fourth contact to one side of a current source, the movable switch element being mounted for relative axial movement toward and away from the stator, the contacts of both sets being so constructed and arranged as to maintain the recited engagement therebetween at said second and third positions regardless of the axial movement of the movable switch element toward and away from the stator, the third and fourth contacts being so constructed and arranged that in the third and second positions they are out of engagement when the movable switch element is moved axially to a first terminal position with respect to the stator and are in engagement when the movable switch element is moved axially to the second terminal position with respect to the stator.

2. A control system for an internal combustion engine, comprising a first, ignition control circuit, a second, starter control circuit, a third circuit for an accessory including an accessory-operating solenoid, and a switch operable selectively to deenergize said three circuits simultaneously, to energize only the first circuit, or to energize the first and second circuits simultaneously, and operable selectively to energize the third circuit simultaneously with either the energization of the first circuit or with the simultaneous energization of the first and second circuits, said switch comprising a stator having a first set of contacts comprising a starter contact in said starter control circuit, an ignition contact in said ignition control circuit, and a first accessory contact in said third circuit, a rotor which may be selectively turned to off, run, and start positions, said rotor having a second set of contacts at least one of which engages the starter contact in the start position of the rotor and at least one of which engages the ignition contact in the start and run positions of the rotor, the rotor having a second accessory contact confronting the first accessory contact when the rotor is in start and run positions, means connecting the second set of contacts and the second accessory contact to one side of a current source, the rotor being mounted for relative axial movement toward and away'fr'orn the stator, the contacts of both sets being so constructed and arranged as to maintain the recited engagement therebetween at said run and start positions regardless of the axial movement of the rotor toward and away from the stator, the first and second accessory contacts being so constructed and arranged thatin the start and run positions they are out of engagement when the rotor is moved axially to a first terminal position with respect to the stator and are in engagement when the rotor is moved axially to the second terminal position with respect to the stator.

3. A control system for an internal combustion engine, comprising a first, ignition control circuit, a second, starter control circuit, a third, choke control circuit including a choke operating solenoid, and a switch selectively operable to deenergize said three circuits simultaneously, to energize only the first circuit, or to energize the first and second circuits simultaneously, and selectively operable to energize the third circuit simultaneously with either the energization of the first circuit or with the simultaneous energization of the first and second circuits, said switch comprising a stator having a first set of contacts comprising a starter contact in said starter control circuit, an ignition contact in said ignition control cir cuit, and a first choke contact in said choke control circuit, and a rotor which may be selectively turned to off, run, and start positions, said rotor having a second set of contacts at least one of which engages the starter contact in the start position of the rotor and at least one of which engages the ignition contact in the start" and run positions of the rotor, the rotor having a second choke contact confronting the first choke contact when the rotor is in start and run positions, means connecting the second set of contacts and the second choke contact to one side of a current source, the rotor being mounted for relative axial movement toward and away from the stator, the contacts of both said sets being so constructed and arranged as to maintain the recited engagement therebetween at said run and start positions regardless of the axial movement of the rotor toward and away from the stator, the first and second choke contacts being so constructed and arranged that in the start and run positions they are out of engagement when the rotor is moved axially to a first terminal position with respect to the stator and are in engagement when the rotor is moved axially to the second terminal position with respect to the stator.

4. A control system comprising a first circuit, a second circuit, a third circuit, a common source of electricalenergy connected to each of said circuits for energizing the same, and a switch having a rotor selectivelyangularly operable to a first position to deenergize said three circuits simultaneously, to a second position to energize only the first circuit, or to a third position to energize the first and second circuits simultaneously, and selectively axially operable from said second and third positions to energize the third circuit simultaneously with either the energization of the first circuit or with the energization of the first and second circuits, said switch comprising a stator extending transversely of the rotor axis, first, second and third contacts on the stator connected in said first, second and third circuits, respectively, a common contact on said stator connected to said source, resilient means for yieldably urging the rotor axially in one direction to a normal terminal position, bridging contacts mounted on the rotor for continuous yieldable sliding engagement with the stator to selectively operatively connect said common contact to said first and second contacts on the stator to close said first and second circuits, and a resiliently yieldable bridging contact mounted on the rotor for yieldable engagement with the stator only when the rotor is moved axially from said normal terminal position to operatively connect said third contact to said common contact to close said third circuit.

5. A control system for an internal combustion engine, comprising a first, ignition control circuit, a second, starter control circuit, a third circuit for an accessory including an accessory-operating solenoid, a common source of electrical energy connected in each of said circuits for energizing the same, and a switch having a rotor operable selectively to a first angular position to deenergize said three circuits simultaneously, to a second angular position to energize only the first circuit, or to a third angular position to energize the first and second circuits simultaneously, and axially operable selectively when in said second and third angular positions to energize the third circuit simultaneously with either the energization of the first circuit or with the simultaneous energization of the first and second circuits.

References Cited in the file of this patent UNITED STATES PATENTS Douglas Aug. 11, 1931 Moncrief July 6, 1948 Taylor May 7, 1957 NeWlin May 27, 1958 I-lefler Apr. 15, 1960 

1. A CONTROL SYSTEM COMPRISING A FIRST CIRCUIT, A SECOND CIRCUIT, A THIRD CIRCUIT, AND A SWITCH OPERABLE SELECTIVELY TO DEENERGIZE SAID THREE CIRCUITS SIMULTANEOUSLY, TO ENERGIZE ONLY THE FIRST CIRCUIT, OR TO ENERGIZE THE FIRST AND SECOND CIRCUITS SIMULTANEOUSLY, AND OPERABLE SELECTIVELY TO ENERGIZE THE THIRD CIRCUIT SIMULTANEOUSLY WITH EITHER THE ENERGIZATION OF THE FIRST CIRCUIT OR WITH THE SIMULTANEOUS ENERGIZATION OF THE FIRST AND SECOND CIRCUITS, SAID SWITCH COMPRISING A STATOR HAVING A FIRST SET OF CONTACTS COMPRISING A FIRST CONTACT IN SAID FIRST CIRCUIT, A SECOND CONTACT IN SAID SECOND CIRCUIT, AND A THIRD CONTACT IN SAID THIRD CIRCUIT, A SWITCH ELEMENT WHICH MAY BE SELECTIVELY MOVED RELATIVE TO THE STATOR TO FIRST, SECOND, AND THIRD POSITIONS, SAID MOVABLE SWITCH ELEMENT HAVING A SECOND SET OF CONTACTS AT LEAST ONE OF WHICH ENGAGES THE FIRST CONTACT IN THE THIRD POSITION OF THE MOVABLE SWITCH ELEMENT AND AT LEAST ONE OF WHICH ENGAGES THE SECOND AND FIRST CONTACTS IN THE THIRD AND SECOND POSITIONS RESPECTIVELY OF THE MOVABLE SWITCH ELEMENT, THE MOVABLE SWITCH ELEMENT HAVING A FOURTH CONTACT CONFRONTING THE THIRD CONTACT WHEN THE MOVABLE SWITCH ELEMENT IS IN ITS THIRD AND SECOND POSITIONS, MEANS CONNECTING THE SECOND SET OF CONTACTS AND THE FOURTH CONTACT TO ONE SIDE OF A CURRENT SOURCE, THE MOVABLE SWITCH ELEMENT BEING MOUNTED FOR RELATIVE AXIAL MOVEMENT TOWARD AND AWAY FROM THE STATOR, THE CONTACTS OF BOTH SETS BEING SO CONSTRUCTED AND ARRANGED AS TO MAINTAIN THE RECITED ENGAGEMENT THEREBETWEEN AT SAID SECOND AND THIRD POSITIONS REGARDLESS OF THE AXIAL MOVEMENT OF THE MOVABLE SWITCH ELEMENT TOWARD AND AWAY FROM THE STATOR, THE THIRD AND FOURTH CONTACTS BEING SO CONSTRUCTED AND ARRANGED THAT IN THE THIRD AND SECOND POSITIONS THEY ARE OUT OF ENGAGEMENT WHEN THE MOVABLE SWITCH ELEMENT IS MOVED AXIALLY TO A FIRST TERMINAL POSITION WITH RESPECT TO THE STATOR AND ARE IN ENGAGEMENT WHEN THE MOVABLE SWITCH ELEMENT IS MOVED AXIALLY TO THE SECOND TERMINAL POSITION WITH RESPECT TO THE STATOR. 